Ibogaine effects on sweet preference and amphetamine induced locomotion: implications for drug addiction.
The neural basis of ibogaine's effects on drug-related behaviours is unclear. One possibility is that ibogaine interferes with the shared capacity of many addictive agents to stimulate brain dopamine activity, but reports of ibogaine effects on dopamine activity have been inconsistent. Our study suggests such inconsistencies may result from variations in prior drug exposure. If ibogaine blocks dopamine activity, then it should, like dopamine blockers, decrease preference for natural rewards such as sweet solutions. However, 40 mg/kg ibogaine i.p. did not decrease preference for a glucose + saccharin solution when it was administered to male Long Evans rats 24 h prior to test in Experiment 1. Nor did ibogaine attenuate conditioned preference for a neutral flavour previously paired with sweet taste in Experiment 2. In Experiment 3, effects of 40 mg/kg ibogaine on amphetamine-induced locomotion were investigated in drug-naive and drug-experienced (four prior doses of 1.5 mg/kg amphetamine) rats. Locomotion was significantly lower in those ibogaine-treated rats that had previously been exposed to amphetamine than in those that had not. Thus, ibogaine may serve to decrease induced levels of dopamine activity in drug-experienced animals or humans from elevated, sensitized levels back to baseline levels. This could lead to a reduction of sensitized levels of drug craving in addiction.
Blackburn
J R
JR
Department of Psychology, McMaster University, Hamilton, Ontario, Canada. jrblackb@is2.dal.ca
Szumlinski
K K
KK
D000661:Amphetamine / Q000494:pharmacology*; D000818:Animals; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003463:Cues; D004298:Dopamine / Q000502:physiology; D018492:Dopamine Antagonists / Q000494:pharmacology; D004347:Drug Interactions; D005518:Food Preferences / Q000187:drug effects*; D007050:Ibogaine / Q000494:pharmacology*; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D011619:Psychotropic Drugs / Q000494:pharmacology*; D051381:Rats; D012201:Reward; D019966:Substance-Related Disorders / Q000523:psychology*; D009435:Synaptic Transmission / Q000187:drug effects; D013649:Taste / Q000187:drug effects*
D000697:Central Nervous System Stimulants; D018492:Dopamine Antagonists; D011619:Psychotropic Drugs; D007050:Ibogaine; D000661:Amphetamine; D004298:Dopamine